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Novel electromagnetism-like mechanism method for multiobjective optimization problems 被引量:1
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作者 lixia han Shujuan Jiang Shaojiang Lan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期182-189,共8页
As a new-style stochastic algorithm, the electromagnetism-like mechanism(EM) method gains more and more attention from many researchers in recent years. A novel model based on EM(NMEM) for multiobjective optimizat... As a new-style stochastic algorithm, the electromagnetism-like mechanism(EM) method gains more and more attention from many researchers in recent years. A novel model based on EM(NMEM) for multiobjective optimization problems is proposed, which regards the charge of all particles as the constraints in the current population and the measure of the uniformity of non-dominated solutions as the objective function. The charge of the particle is evaluated based on the dominated concept, and its magnitude determines the direction of a force between two particles. Numerical studies are carried out on six complex test functions and the experimental results demonstrate that the proposed NMEM algorithm is a very robust method for solving the multiobjective optimization problems. 展开更多
关键词 electromagnetism-like mechanism(EM) method multi-objective optimization problem PARTICLE Pareto optimal solutions
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外来物种入侵与本土物种分布区扩张的异同
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作者 韩丽霞 王永健 刘宣 《生物多样性》 CAS CSCD 北大核心 2024年第1期130-145,共16页
当今全球变化背景下,物种分布区正发生着快速变化,一类是人类活动介导下的生物入侵过程,另一类是本土物种的自然分布区扩张。两者之间既具有相似之处,亦有明显差异。探讨两者间异同是发展外来入侵物种管控和本土物种保护策略的基础科学... 当今全球变化背景下,物种分布区正发生着快速变化,一类是人类活动介导下的生物入侵过程,另一类是本土物种的自然分布区扩张。两者之间既具有相似之处,亦有明显差异。探讨两者间异同是发展外来入侵物种管控和本土物种保护策略的基础科学问题。本文以两栖爬行类、鸟类和哺乳类等陆栖脊椎动物为例,在阐述外来物种入侵过程的基础上,将其与本土物种的分布区变化进行比较并阐述了两者间的异同。我们发现,伴随经济贸易发展和人口流动,外来物种正在加剧入侵;同时,发生分布范围变化的本土物种数量也在迅速增加。两者在分布区变化过程中的驱动因子、时空尺度、发生速度、物种特征的预测能力以及对新分布区的影响方面具有明显差异:人类活动介导下的外来物种入侵通常会经历长距离迁移,甚至跨越生物地理区系,并在入侵区快速扩散,物种特征在预测外来物种入侵过程中起着重要作用,对当地生物多样性造成严重威胁;本土物种分布区扩张通常发生在原生范围的邻近区域,发生速度较慢,物种特征在预测分布区扩展中的作用有限,且对新区域的负面影响较小。由于在短期内很难全面判定外来物种和发生分布区变化的本土物种的生态影响,我们建议应对新分布区内的外来物种和本土物种进行密切监测和长期研究,对其可能引发的生态学效应进行早期预警和评估,以最大限度地限制其潜在危害并保护生物多样性。 展开更多
关键词 生物入侵 生物多样性保护 全球变化 生态位动态 分布区扩张
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Characterization of a new smog chamber for evaluating SAPRC gas-phase chemical mechanism
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作者 Kangwei Li Chao Lin +8 位作者 Chunmei Geng Stephen White Linghong Chen Zhier Bao Xin Zhang Yanyun Zhao lixia han Wen Yang Merched Azzi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第9期14-22,共9页
A new state-of-the-art indoor smog chamber facility(CAPS-ZJU) has been constructed and characterized at Zhejiang University,which is designed for chemical mechanism evaluation under well-controlled conditions.A series... A new state-of-the-art indoor smog chamber facility(CAPS-ZJU) has been constructed and characterized at Zhejiang University,which is designed for chemical mechanism evaluation under well-controlled conditions.A series of characterization experiments were performed to validate the well-established experimental protocols,including temperature variation pattern,light spectrum and equivalent intensity(JNO2),injection and mixing performance,as well as gases and particle wall loss.In addition,based on some characterization experiments,the auxiliary wall mechanism has been setup and examined.Fifty chamber experiments were performed across a broad range of experimental scenarios,and we demonstrated the ability to utilize these chamber data for evaluating SAPRC chemical mechanism.It was found that the SAPRC-11 can well predict the 03 formation and NO oxidation for almost all propene runs,with 6 hr △(O3-NO) model error of-3%±7%,while the final O3 was underestimated by-20% for isoprene experiments.As for toluene and p-xylene experiments,it was confirmed that SAPRC-11 has significant improvement on aromatic chemistry than earlier version of SAPRC-07,although the aromatic decay rate was still underestimated to some extent.The model sensitivity test has been carried out,and the most sensitive parameters identified are the initial concentrations of reactants and the light intensity as well as HONO offgasing rate and 03 wall loss rate.All of which demonstrated that CAPS-ZJU smog chamber could derive high quality experimental data,and could provide insights on chamber studies and chemical mechanism development. 展开更多
关键词 MECHANISM CHEMICAL CAPS
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